In City Hall, Koch embraced New York for the rest of the world. He won a national reputation with his feisty style and his trademark question, "How'm I doing?"

During his years as mayor, from 1978 to 1989, his tight fiscal policies pulled the city out of severe financial difficulties. But homelessness and racial tensions soared and critics charged that City Hall's responses were ineffective.

Koch's mark on the city was set in steel when the Queensboro Bridge, connecting Manhattan to Queens, was renamed in his honor in 2011.